Diagnostic ultrasound ( PDFDrive )

CHAPTER 21 The Breast 789
within loose periductal stromal tissues, and between tissue planes
within the ibrous tissue (Fig. 21.44B-C). A single angle of any
type on the surface of the lesion should be considered suspicious.
he presence of angular margins has the greatest individual
sensitivity and overall accuracy of any of the features. 45
Microlobulations
Microlobulations are 1-mm to 2-mm lobulations that vary in
number and distribution along the surface and within the
substance of a mass. Microlobulations are a subcategory of the
ACR BI-RADS category “Margin–Not Circumscribed.” 17 hey
may occur over only a small percentage of the surface of a nodule.
Microlobulation is a mixed inding that can be seen with both
invasive and DCIS components of tumor, but more oten represents
in situ components of tumor. When microlobulations
are angular and are associated with a thick echogenic rim, they
usually represent ingers of invasive carcinoma 45 (Fig. 21.45A).
When the microlobulations are rounded and associated with a
thin echogenic capsule, they usually represent DCIS components
of tumors. DCIS components can create microlobulations in
two ways: involved lobules (Fig. 21.45B), or ductules or ducts
that are distended with tumor and necrosis (Fig. 21.45C-D).
FIG. 21.41 Echogenic Rim With Hyperechoic Spicules. The thick,
poorly deined echogenic rim that can be seen around some invasive
malignant lesions surrounded by fat represents hyperechoic spicules
too small to be resolved individually. The rim is more often seen and is
thicker along the sides of the nodule within the coronal plane (arrows)
because spicules are more common in the coronal plane and because
the spicules that lie within the coronal plane are perpendicular to the
ultrasound beam, where they make strong specular relectors.
Not Parallel (Not Taller-Than-Wide) Orientation
Lesions that are larger in the AP dimension than in any horizontal
dimension are considered not parallel and are suspicious for
malignancy. Round masses are also viewed as not parallel in
their orientation. Not parallel orientation is unique to sonography
and is not seen on mammography. It is a subcategory of the
ACR BI-RADS category “Orientation.” 17 his is a mixed inding
that can be seen with both invasive and DCIS lesions (Fig. 21.46).
his orientation is primarily a feature of small, solid malignant
FIG. 21.42 Three-Dimensional or Volume Imaging With a Hand-Held Transducer. The coronal reconstructed plane can be especially useful
in assessing for spiculations. What appears to be a poorly deined, thick, echogenic rim in radial or antiradial planes (left, arrows), can often be
resolved as individual hyperechoic spicules in the reconstructed coronal plane (right, arrows). The coronal plane can also better demonstrate other
architectural distortions, such as thickened Cooper ligaments (right, arrowheads).